Greater London is a ceremonial county of England that makes up the majority of the London region. This region forms the administrative boundaries of London and is organised into 33 local government districts—the 32 London boroughs and the City of London, which is located within the region but is separate from the county. The Greater London Authority, based in Southwark, is responsible for strategic local government across the region and consists of the Mayor of London and the London Assembly. The City of London Corporation is the principal local authority for the City of London, with a similar role to that of the 32 London borough councils.
High resolution view from the top of Tolworth Tower in South West London over the sprawling suburban housing that is typical in some areas of Greater London
Greater London is also a region of England that can also be known as the London region. The London region can also be counted as part of South East region.
With increasing industrialisation, London's population grew rapidly throughout the 19th and early 20th centuries, and it was the most populated city in the world until overtaken by New York in 1925. Its population peaked at 8,615,245 in 1939. There were an estimated 7,753,600 official residents in mid-2009.
Administratively, Greater London was first established as a sui generis council area under the Greater London Council between 1963 and 1986. The county of Greater London was created on 1 April 1965 through the London Government Act 1963. The area was re-established as a region in 1994. The Greater London Authority was formed in 2000.
London's wider metropolitan area has a population of between 12 and 14 million depending on the definition of that area. According to Eurostat, London has been the most populous city and metropolitan area of the European Union.
The region covers 1,572 km2 and had a population of 8,174,000 at the 2011 census. The Greater London Built-up Area is used in some national statistics and is a measure of the continuous urban area and includes areas outside the administrative region.
The region covers an area of 1,579 square kilometres. The population density is 4,761 people per square kilometre, more than ten times that of any other British region. In terms of population, London is the 25th largest city and the 17th largest metropolitan region in the world. It is ranked 4th in the world in the number of US dollar billionaires residing in the city. It ranks as one of the most expensive cities in the world, alongside Tokyo and Moscow.